By default do not use multithreaded wxtgtk （commit [8fc9b3]）

[Tatsuro M. <tma...@ya...>]

In development source,
commit [8fc9b3]

By default do not use multithreaded wxtgtk 

I have been using --with-wx-single-threaded for Unixy build for a long time.

Is there any plan that this commit will be back-ported to stable source?

Tatsuro